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1.
ACS Appl Mater Interfaces ; 15(51): 59973-59980, 2023 Dec 27.
Article in English | MEDLINE | ID: mdl-38100997

ABSTRACT

Spent coffee grounds are recognized as a green and sustainable resource of cellulose nanofiber (CNF), which can further form aerogels with rGO for solar-driven interfacial desalination via directional freezing technology. The vertically arranged channels provide better photothermal conversion performance and salt tolerance of rGO/CNF aerogels. Their max evaporation rate can reach to 2.729 kg·m-2·h-1 under natural sunlight. In terms of long-term application (10 days), the aerogels exhibit a stable evaporation property in outdoor environments. The optimum daily average water yield is 15.00 L·m-2, which can fulfill the daily water requirement of six people.

2.
Front Psychiatry ; 14: 1242611, 2023.
Article in English | MEDLINE | ID: mdl-38034924

ABSTRACT

Background: Behavioral patterns are sometimes associated with depression symptoms; however, few studies have considered the intra-couple effects. This study examined the effect of a spouses' behavioral patterns on depression symptoms within themself and in their spouse. Methods: A total of 61,118 childbearing age participants (30,559 husband-wife dyads) were surveyed. The depression symptoms were assessed using the nine-item Patient Health Questionnaire (PHQ-9). The behavioral patterns were identified by the latent class analysis. The effects of behavioral patterns on the couple's own depression symptoms (actor effect) and their partner's depression symptoms (partner effect) were analyzed using the Actor-Partner Interdependence Model (APIM). Results: Three behavioral patterns were identified: low-risk group, moderate-risk group, and high-risk group. The high risk of these behavior patterns would be associated with a higher score on the PHQ-9; for both husbands and wives, their behavioral patterns were positively associated with PHQ-9 scores (ßhusband = 0.53, P < 0.01; ßwife = 0.58, P < 0.01). Wives' behavioral patterns were also positively associated with their husbands' PHQ-9 scores (ß = 0.14, P < 0.01), but husbands' behavioral patterns were not associated with their wives' PHQ-9 scores. Conclusions: Wives' depression symptoms were affected only by their own behavioral patterns, whereas husbands' depression symptoms were influenced by both their own and their spouses' behavioral patterns.

3.
J Hazard Mater ; 460: 132322, 2023 Oct 15.
Article in English | MEDLINE | ID: mdl-37657320

ABSTRACT

Sb and its compounds have been widely used in various industrial applications. Therefore, the preparation of Sb adsorbents with easy recovery and excellent adsorption levels is an urgent problem that must be resolved. By calcining and treating La/Fe metal-organic frameworks (MOF) biochar as a precursor, a loaded La-Fe-modified water hyacinth biochar was synthesised and used as a filler to synthesise iron alginate composite gel spheres, MBC/algFe. Through a series of static adsorption experiments, the effects of different filler addition ratios, solution pH, reaction time, coexisting ions, and other factors on the adsorption of Sb(III) were investigated. According to the Langmuir model, the maximum adsorption capacity of MBC/algFe at 25 â„ƒ was 277.8 mg·g-1. The adsorption mechanism mainly involved hydrogen bonding and metal-organic complexation interactions.

4.
J Colloid Interface Sci ; 650(Pt B): 1993-2002, 2023 Nov 15.
Article in English | MEDLINE | ID: mdl-37531666

ABSTRACT

Photocatalytic fuel cells (PFCs) convert organic waste into electricity, thereby providing a potential solution for remediating environmental pollution and solving energy crises. Most PFCs for energy generation applications use powder photocatalysts, which have poor mechanical stability, high internal resistance, and may detach from the substrate during reactions, leading to unstable performance. Integrated photoelectrodes can overcome the drawbacks of powder catalysts. In this study, an integrated photoanode was prepared based on a silicon nanowire arrays/zinc oxide (Si NWs/ZnO) heterojunction by combining metal-assisted chemical etching (MACE) and hydrothermal methods. The resulting photoanode was used to assemble a PFC for simultaneous electricity generation and Rhodamine (RhB) dye wastewater degradation. This PFC showed excellent cell performance under irradiation, with a short-circuit current density of 0.183 Am-2, an open-circuit voltage (OCV) of 0.72 V, and a maximum power density of 0.87 W m-2. It could also be used continuously 20 times while degrading > 90% of RhB. This performance was ascribed to the three-dimensional (3D) structure and large surface area of Si NWs, as well as the matched band structure of ZnO, which facilitated the efficient separation and transport of photogenerated carriers in Si NWs/ZnO. The integrated structure also shortened the carrier transport pathways and suppressed carrier recombination. This research provides a foundation for the development of efficient, stable, low-cost, small-scale PFCs.

5.
Anal Bioanal Chem ; 415(22): 5353-5363, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37389597

ABSTRACT

A new type of hexafluorobutanol (HFB) primary alcohol ethoxylate (AEO)-based supramolecular solvent (SUPRAS) with density higher than water was prepared for the first time. HFB acted as AEO micelle-forming agent and density-regulating agent for SUPRAS formation. The prepared SUPARS was applied as extraction solvent for vortex-assisted direct microextraction of malachite green (MG) and crystal violet (CV) from lake sediment followed by high-performance liquid chromatographic determination. In the present work, SUPRASs prepared from AEO with different carbon chains as the amphiphiles and various coacervation agents were investigated. SUPARS formed from MOA-3 and HFB provided better extraction efficiency in comparison with other SUPRASs. Parameters influencing the extraction recovery of target analytes including the type and volume of AEO, volume of HFB, and vortex time were investigated and optimized. Under optimized conditions, linearity in the range of 2.0-400 µg g-1 for MG and 2.0-500 µg g-1 for CV with a correlation coefficient higher than 0.9947 was obtained. Limits of detection of 0.5 µg g-1 and relative standard deviations in the range of 0.9-5.8% were obtained. Compared to conventional extraction techniques for analysis of analytes in solid samples, the proposed method reduced sample usage and eliminated a primary extraction process by using a toxic organic solvent. The proposed method is simple, fast, and green and can be used for the analysis of target analytes in solid samples.

6.
Luminescence ; 38(8): 1501-1510, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37292009

ABSTRACT

To better understand the relationship between molecular structure and mechanofluorochromic characteristics, three carbazole-based N^O-chelated difluoroboron compounds (Cz-S-BF2 , Cz-PhNp-S-BF2 , and Cz-BNp-S-BF2 ) with different aryl substituents moieties were designed and synthesized. The mechanofluorochromic behaviours of Cz-S-BF2 (luminescence from bluish-green to yellowish-green, emission from 504 to 535 nm) without aryl substitution and Cz-PhNp-S-BF2 (luminescence from green and yellow, emission from 521 to 557 nm) with a phenyl-naphthalene group underwent reversible conversion using the grinding-fuming process. For Cz-BNp-S-BF2 this was not apparent due to the well coplanarity of the binaphthalene moiety. Mechanofluorochromic properties were demonstrated through XRD patterns measurement. We envisage that this study will provide a practicable reference to acquire organic molecules with mechanofluorochromic characteristics.


Subject(s)
Carbazoles , Gases , Luminescence
7.
Int J Mol Sci ; 23(11)2022 Jun 02.
Article in English | MEDLINE | ID: mdl-35682938

ABSTRACT

Optical signals of pH probes mainly driven from the formation or rupture of covalent bonds, whereas the changes in covalent bonds usually require higher chemical driving forces, resulting in limited sensitivity and reversibility of the probes. The exploration of high-performance pH probes has been a subject of intense investigation. Herein, a new pH probe has been developed, with optical property investigation suggesting the probe has excellent signal-to-noise ratio, and fluorescence intensity shows exponential growth, combined with a visible color change, as pH increased from 5.1 to 6.0; Moreover, the probe has outstanding stability and reversibility, with more than 90% of the initial signal intensity remaining after 30 cycles. In order to better understand the special fluorescence behavior of the reported probe, the non-halogenated isomer is introduced for comparison, combined with the results of structural analysis, quantitative calculation and optical experiments, and the possible mechanism of the special supramolecular aggregation-caused quenching effect induced by the halogen atom is discussed.


Subject(s)
Halogens , Schiff Bases , Halogens/chemistry , Hydrogen-Ion Concentration , Isomerism , Schiff Bases/chemistry , Spectrometry, Fluorescence
8.
RSC Adv ; 12(15): 9121-9129, 2022 Mar 21.
Article in English | MEDLINE | ID: mdl-35424865

ABSTRACT

The current study highlights the advantages of using the quality by design (QbD) approach to synthesise and optimize SERS substrates for the detection of Hg2+. Considering that the performance of Au@AgNPs is affected by many factors, Plackett-Burman (PB) experimental design was used to determine the critical process parameters (CPPs) for evaluating the performance of Au@AgNPs. The quantitative relationships between the CPPs and the critical quality attributes (CQAs) were assessed by Box-Behnken Design (BBD). The optimal design space for Au@AgNPs was calculated via a Monte Carlo algorithm. Finally, detection of Hg2+ in the range of 1 ∼ 100 ng mL-1 (R 2 = 0.9891) was achieved by SERS in combination with 4,4-bipyridine (Dpy) as signal molecules. The recoveries for licorice ranged from 83.53% to 92.96%. Specificity and practicality studies indicated that the method based on the QbD concept and design space not only met the optimal performance of Au@AgNPs but also improved the rapid detection of Hg2+ in Chinese medicine samples.

9.
Org Biomol Chem ; 20(5): 1013-1018, 2022 02 02.
Article in English | MEDLINE | ID: mdl-35043137

ABSTRACT

A chemical reductant or a sacrificial electron donor is required in any reduction reactions, generally resulting in undesired chemical waste. Herein, we report a reductant-free reductive [3 + 2 + 1] annulation of ß-keto amides with CS2 enabled by the synergy of electro/copper/base using water as an innocuous anodic sacrifice with O2 as a sustainable by-product. This electrochemical protocol is mild and provides access to polyfunctionalized pyridin-2-ones from simple starting materials in a single step.

10.
Anal Bioanal Chem ; 413(15): 3873-3880, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33963882

ABSTRACT

In this work, a new generation of hydrophobic deep eutectic solvents (DESs) was prepared using eugenol (as hydrogen bond donor) and benzyltriethylammonium bromide, benzyltributylammonium bromide, benzyltriethylammonium chloride and benzyltributylammonium chloride (as hydrogen bond acceptor) in different molar ratios. These DESs were applied to vortex-assisted dispersive liquid-liquid microextraction of Sudan dyes from food samples, followed by high-performance liquid chromatographic determination. The influencing parameters, including the type of DES, amount of DES, extraction time, solution pH and salt addition, were investigated and optimized. Under the optimized conditions, a linear range of 2-1000 ng mL-1 with determination coefficients of <0.999 was obtained. Limits of detection and limits of quantification were in the range of 0.5 to 1 ng mL-1 and 2 to 3 ng mL-1, respectively. The proposed method was successfully used in the determination of Sudan dyes in chili sauce, chili powder and ketchup, and satisfactory recoveries of between 89.9 and 119.3% were obtained, with relative standard deviations in the range of 0.1-6.8%. The proposed method is simple, green and efficient, and can be applied to determine Sudan dyes in complex matrices.


Subject(s)
Coloring Agents/isolation & purification , Food Analysis/methods , Liquid Phase Microextraction/methods , Solvents/chemistry , Chromatography, High Pressure Liquid/methods , Hydrophobic and Hydrophilic Interactions , Limit of Detection , Reference Standards , Spectroscopy, Fourier Transform Infrared
11.
Curr Drug Metab ; 22(3): 224-231, 2021.
Article in English | MEDLINE | ID: mdl-33538667

ABSTRACT

BACKGROUND: Shenqi Jiangtang Granule (SJG), a classical prescription of traditional Chinese medicine, is widely used to treat diabetes and its complications. Although, the clinical efficacy of SJG, is sufficient, the pharmacokinetic behavior of various substances in the plasma of SJG is unknown. OBJECTIVE: The aim of this study was to investigate the plasma pharmacokinetics during absorption of SJG after oral administration in rats. METHODS: A rapid and accurate ultra-high performance liquid chromatography/tandem mass spectrometry (UPLC- MS/MS) method was developed for the simultaneous determination of eight analytes in SJG, including gomisin D, schisandrin A, schisandrin B, schizandrol A, schizandrol B, ginsenoside Rd, ginsenoside Re and notoginsenoside Ft1. The analysis was carried out on a BEH C18 column (2.1 mm × 50 mm, 1.7 µm) with gradient elution at a flow rate of 0.2 mL/min in a mobile phase consisting of 0.1% formic acid water and acetonitrile. In addition, lignans and saponins were detected in positive ion mode and negative ion mode, respectively. RESULTS: Eight analytes in SJG, including gomisin D, schisandrin A, schisandrin B, schizandrol A, schizandrol B, ginsenoside Rd, ginsenoside Re and notoginsenoside Ft1, showed good linearity (R2 in the range of 0.9955 ~ 0.9999). The lower limit of quantification (LLOQ) was 5, 0.8, 0.8, 8, 0.8, 5, 0.6 and 10 ng/mL. The accuracy and precision of all analytes were at ±15%. Matrix effect and average extraction recovery were > 85%. All analytes performed well under four storage conditions. CONCLUSION: The results showed that in vivo absorption and exposure of gomisin D and ginsenoside Rd were better than other analytes, while schizandrol B and notoginsenoside Ft1 were poorly absorbed. This approach could be applied to study the pharmacokinetic characteristics of various analytes in plasma after oral administration of SJG in rats.


Subject(s)
Drugs, Chinese Herbal/pharmacokinetics , Lignans/blood , Saponins/blood , Administration, Oral , Animals , Chromatography, High Pressure Liquid/methods , Drugs, Chinese Herbal/administration & dosage , Drugs, Chinese Herbal/metabolism , Lignans/metabolism , Male , Metabolomics/methods , Models, Animal , Rats , Reproducibility of Results , Saponins/metabolism , Tandem Mass Spectrometry/methods
12.
RSC Adv ; 10(21): 12129-12134, 2020 Mar 24.
Article in English | MEDLINE | ID: mdl-35497584

ABSTRACT

Herein, Ni-MOF sheet incorporated with polypyrrole is fabricated via a simple wet-chemical approach, and the obtained PPy-MOF composite is investigated as an electrode material for supercapacitors. The composite is systematically investigated by a series of characterization studies including X-ray diffraction, scanning electron microscopy, and X-ray photoelectron spectroscopy. Besides that, the electrochemical capacitive behaviors of the products are examined by electrochemical measurements. Electrochemical results show varying the ingredient ratio can lead to different electrocapacitive behavior, and PPy-MOF-0.2 is proved to possess the best performance in the investigated recipes. Furthermore, an asymmetric supercapacitor employing PPy-MOF and activated carbon as positive and negative electrodes is also assembled, which exhibits high energy density.

13.
Sci Total Environ ; 684: 629-640, 2019 Sep 20.
Article in English | MEDLINE | ID: mdl-31170597

ABSTRACT

Ammonia-oxidizing archaea (AOA) microorganisms have been increasingly found in aquatic and terrestrial environments. These microorganisms make vital contributions to ammonia oxidation in such systems. However, their community succession characteristics in man-made wetland ecosystems have scarcely been reported. We assessed the AOA's spatiotemporal shifts in the sediments of a constructed wetland (CW) - the Shijiuyang constructed wetland (SJY-CW) - in China from the third year (2011) to the fifth year (2013) of the CW operation. The SJY-CW is composed of a pretreatment pond, a multiple plant-bed/ditch system, and a post-treatment pond. Results showed that AOA abundance in the pre- and post-treatment ponds remained invariant through 2011-2012 and decreased in 2013, while the abundance in the plant-bed/ditch system decreased gradually with wetland operation. The AOA abundance in 2013 was one order of magnitude lower than that through 2011-2012, and the AOA abundance in the plant-bed/ditch system was generally higher than that in the pre- and post-treatment ponds from 2011 to 2013. AOA diversity showed little temporal differentiation with a slightly decreasing trend for community richness index Chao1 and diversity index Shannon H' from 2011 to 2013. The AOA community was dominated by the Nitrososphaera cluster accompanied by an increasing Nitrosopumilus cluster and Nitrososphaera sister cluster within the wetland operation. Hierarchical clustering and redundancy analysis verified the horizontal shifts of AOA communities. The shifts occurred preferentially in the central plant-bed/ditch system. The operational duration of the wetland became a key factor influencing AOA abundance and community shift in SJY-CW sediments.


Subject(s)
Archaea/physiology , Conservation of Natural Resources , Microbiota , Wetlands , Ammonia/metabolism , Archaea/classification , Oxidation-Reduction , Population Dynamics , Spatio-Temporal Analysis
14.
Chem Asian J ; 14(11): 1932-1936, 2019 Jun 03.
Article in English | MEDLINE | ID: mdl-31046195

ABSTRACT

A rare example of C(sp3 )-H functionalization of simple alkanes with unactivated alkenes is presented. In the presence of a copper salt and di-tert-butyl peroxide (DTBP), N-allyl anilines underwent exo-selective alkylation/cyclization cascade with unactivated alkenic bonds as radical acceptors and simple alkanes as radical precursors, providing a direct access to 3-alkyl indolines. The present protocol features simple operation, broad substrate scope and great exo selectivity.

15.
J Colloid Interface Sci ; 552: 179-185, 2019 Sep 15.
Article in English | MEDLINE | ID: mdl-31125828

ABSTRACT

In this study, ultrathin two-dimensional (2D) bismuth tungstate (Bi2WO6) nanosheets were adopted as a Pt support for photo-assisted electrocatalytic methanol oxidation. Compared with traditional electrocatalytic reactions, the photo-assisted electrocatalytic methanol oxidation reactions of Pt-2D Bi2WO6 nanosheets under simulated solar light and visible light irradiation were improved 5.1 and 2.0 times, respectively. The better photo-assisted electrocatalytic methanol oxidation activities of Pt-Bi2WO6 nanosheets can be attributed to the unique 2D structure that strengthens the oxidation ability of photogenerated holes, reduces the time required for carrier migration, reduces the recombination rate of carriers and provides a larger specific surface area. Additionally, our experimental results reveal the critical factors of photo-assisted enhanced electrocatalytic activities for methanol oxidation and provide a new way to improve the photo-assisted electrocatalytic activities for methanol oxidation.

16.
J Org Chem ; 84(10): 6072-6083, 2019 05 17.
Article in English | MEDLINE | ID: mdl-31021621

ABSTRACT

An unprecedented benzylic C-H functionalization of methyl arenes across unactivated alkenes is presented. In the presence of MnCl2·4H2O and di- tert-butyl peroxide, N-allyl anilines underwent benzylation/cyclization cascade to give benzylated indolines, which are a previously unmet synthetic goal. This protocol features simple operation, broad substrate scope, and great exo selectivity.

17.
J Org Chem ; 83(8): 4681-4691, 2018 04 20.
Article in English | MEDLINE | ID: mdl-29579385

ABSTRACT

A silver-catalyzed phosphorylation/cyclization cascade of N-allyl anilines was developed, allowing direct access to 3-phosphonoalkyl indolines, which were previously obtainable only via tedious procedures under harsh/toxic conditions. The unactivated double bond serves as the radical acceptor, whereas H-phosphonates or -phosphine oxides act as the radical precursor. This protocol features simple operation, broad substrate scope, and great exo selectivity, and a gram-scale synthesis could be readily carried out.

18.
Article in English | MEDLINE | ID: mdl-29328954

ABSTRACT

Although stereoselective antibody has immense potential in chiral compounds detection and separation, the interaction traits between stereoselective antibody and the corresponding antigenic enantiomers are not yet fully exploited. In this study, the stereospecific interactions between ofloxacin isomers and corresponding monoclonal antibodies (McAb-WR1 and McAb-MS1) were investigated using time-resolved fluorescence, steady-state fluorescence, and circular dichroism (CD) spectroscopic methods. The chiral recognition discrepancies of antibodies with ofloxacin isomers were reflected through binding constant, number of binding sites, driving forces and conformational changes. The major interacting forces of McAb-WR1 and McAb-MS1 chiral interaction systems were hydrophobic force and van der Waals forces joined up with hydrogen bonds, respectively. Synchronous fluorescence spectra and CD spectra results showed that the disturbing of tyrosine and tryptophan micro-environments were so slightly that no obvious secondary structure changes were found during the chiral hapten binding. Clarification of stereospecific interaction of antibody will facilitate the application of immunoassay to analyze chiral contaminants in food and other areas.


Subject(s)
Anti-Bacterial Agents/chemistry , Antibodies, Monoclonal/immunology , Ofloxacin/chemistry , Spectrometry, Fluorescence/methods , Anti-Bacterial Agents/immunology , Anti-Bacterial Agents/metabolism , Binding Sites , Hydrogen Bonding , Models, Molecular , Ofloxacin/immunology , Ofloxacin/metabolism , Protein Binding , Stereoisomerism , Thermodynamics
19.
Analyst ; 140(4): 1037-45, 2015 Feb 21.
Article in English | MEDLINE | ID: mdl-25553733

ABSTRACT

In this study, ofloxacin stereoisomers were chosen as a simple model to investigate the stereospecific recognition of chiral haptens and antibodies. Three polyclonal antibodies were studied and showed a relatively high enantioselectivity and an excellent sensitivity. Comparative molecular field analysis and comparative molecular similarity indices analysis were employed to investigate the chiral recognition between the antibody and the ofloxacin enantiomer, and all the models yielded high correlation and predictive ability. It was found that the chiral discrimination was probably caused by steric hindrance; the antibody stereospecificity could be ascribed to the variation of the R1 and R3 groups of quinolones; the common structure of the quinolones is also essential in the hapten-antibody recognition. The recognition between the chiral haptens and the antibodies was co-affected by multiple interaction forces, and those forces were defined explicitly at the sub-structural level. An illustrative enhanced model with good simplicity and universality was also developed for a better understanding of the stereospecific recognition of ofloxacin enantiomers and antibodies for the first time. This work provides insights into the stereospecific recognition of chiral haptens and antibodies.


Subject(s)
Antibodies/immunology , Haptens/immunology , Ofloxacin/immunology , Antibodies/chemistry , Haptens/chemistry , Models, Molecular , Ofloxacin/chemistry , Quantitative Structure-Activity Relationship , Stereoisomerism
20.
Springerplus ; 3: 326, 2014.
Article in English | MEDLINE | ID: mdl-25032090

ABSTRACT

Constructed root-channel wetland (CRCW) is a term for pre-pond/wetland/post-pond complexes, where the wetland includes plant-bed/ditch landscape and root-channel structure. Source water out of pre-ponds flows through alternate small ditches and plant beds with root-channels via a big ditch under hydraulic regulation. Then source water flows into post-ponds to finish final polishing. This article aims to explore the potential of components of a pilot CRCW in China on mitigating metals in micro-polluted source water during its initial operation stage. We investigated six heavy metals (Cd, Cr, Cu, Ni, Zn, and Pb) in surface sediment, plant-bed subsurface soil, water, and aquatic plants during 2012-2013. Monitoring results showed that pond/ditch sediments and plant-bed soil retained a significant amount of Cr, Ni, and Zn with 93.1%, 72.4%, and 57.5% samples showing contamination factor above limit 1 respectively. Remarkably the high values of metal enrichment factor (EF) occurred in root-channel zones. Water monitoring results indicated that Ni, Zn, and Pb were removed by 78.5% (66.7%), 57.6% (59.6%), and 26.0% (7.5%) in east (west) wetland respectively. Mass balance estimation revealed that heavy metal mass in the pond/ditch sediments accounted for 63.30% and that in plant-bed soil 36.67%, while plant uptake occupied only 0.03%. The heavy metal accretion flux in sediments was 0.41 - 211.08 µg · cm(-2) · a(-1), less than that in plant-bed soil (0.73 - 543.94 µg · cm(-2) · a(-1)). The 1.83 ha wetland has retained about 86.18 kg total heavy metals within 494 days after operation. This pilot case study proves that constructed root-channel wetland can reduce the potential ecological risk of purified raw water and provide a new and effective method for the removal of heavy metals from drinking water sources.

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